Hi John,
No, indeed there is no functionality behind this field.
Even if this field is set to "Debit" you still can post "Credit" (and vice versa)
However ... you can filter of this field, in case you want to take a look at G/L Accounts only, which "ususally" have a debit or a credit balance ... for example whenyou are in the process of creating an account schedule.
Does this answer your question?
Thanks
Dirk